Life-cycle of Ixodes scapularis (a.k.a. blacklegged or deer tick)

Life-cycle of Ixodes scapularis(a.k.a. blacklegged or deer tick) in the northeast/mid-Atlantic/upper mid-western United States. Larval deer ticks
are active in August and September but these ticks are pathogen-free. Ticks become infected with pathogens when larvae (or nymphs) take a blood meal from
infectious animal hosts. Engorged larvae molt over winter and emerge in May as poppy-seed sized nymphal deer ticks. Please note that most cases of
Lyme disease are transmitted from May through July, when nymphal-stage ticks are active. Adult-stage deer ticks become active in October and remain
active throughout the winter whenever the ground is not frozen. Blood-engorged females survive the winter in the forest leaf litter and begin laying their 1,500 or more
eggs around Memorial Day (late May). These eggs hatch in July, and the life-cycle starts again when larvae become active in August. Download the print version of Life-cycle of Ixodes scapularis - 2.2 MB